A review and critique of U.S. EPA's risk assessments for asbestos

U.S. Environmental Protection Agency (EPA) recently conducted a risk assessment for exposure to Libby amphibole asbestos that is precedent-setting for two reasons. First, the Agency has not previously conducted a risk assessment for a specific type of asbestos fiber. Second, the risk assessment includes not only an inhalation unit risk (IUR) for the cancer endpoints, but also a reference concentration (RfC) for nonmalignant disease. In this paper, we review the procedures used by the Agency for both cancer and nonmalignant disease and discuss the strengths and limitations of these procedures. The estimate of the RfC uses the benchmark dose method applied to pleural plaques in a small subcohort of vermiculite workers in Marysville, Ohio. We show that these data are too sparse to inform the exposure–response relationship in the low-exposure region critical for estimation of an RfC, and that different models with very different exposure–response shapes fit the data equally well. Furthermore, pleural plaques do not represent a disease condition and do not appear to meet the EPA's definition of an adverse condition. The estimation of the IUR for cancer is based on a subcohort of Libby miners, discarding the vast majority of lung cancers and mesotheliomas in the entire cohort and ignoring important time-related factors in exposure and risk, including effect modification by age. We propose that an IUR based on an endpoint that combines lung cancer, mesothelioma, and nonmalignant respiratory disease (NMRD) in this cohort would protect against both malignant and nonmalignant disease. However, the IUR should be based on the entire cohort of Libby miners, and the analysis should properly account for temporal factors. We illustrate our discussion with our own independent analyses of the data used by the Agency.     

Staff knowledge,attitudes and practices regarding glycaemic management in adult intensive care units: A national survey

Background

Hyperglycaemia is common in critically ill adult patients. Many studies have identified the content, methods, and effects of glycaemic control but have not explored the effects of knowledge, attitudes, and practices (KAP) on glycaemic control in critically ill adults. Various factors also influence the KAP of intensive care unit (ICU) staff.

Aims

To assess KAP regarding glucose management for critically ill adults among nurses and medical professionals and identify the factors that influence their KAP in ICUs.

Methods

A multicentre cross-sectional survey.

Results

In total, 403/459 (response rate: 87.8%) participants from ICUs in nine tertiary hospitals in China participated in this study, 82.4% of whom were female and 93.4% of whom were nurses. The mean work experience was 8.88 years, and the mean critical care experience was 6.59 years. The scoring rate for the three dimensions of knowledge, attitudes, and practices were 82.35%, 87.69%, and 76%, respectively. We did not find any other factors affecting the KAP scores except for the level of knowledge awareness (p < 0.001), awareness of the importance (p < 0.001), and training for glucose control (p = 0.004).

Conclusion

ICU staff KAP regarding glycaemic control in critically ill adults among ICU professionals were acceptable in China. However, ICU professionals' current knowledge regarding nutrition, glucose variability, and skills related to glucose management could be improved.

Relevance to Clinical Practice

ICU educators should provide more skills-related training for healthcare professionals in the glycaemic management of critically ill adults. Moreover, the process of managing blood glucose in adult ICU patients is a collaborative, multidisciplinary team effort, with monitoring and feedback required during implementation.     

Three-dimensional speckle-tracking echocardiography for evaluating myocardial motion in patients with cardiorenal syndrome

Because of better awareness and understanding of its pathophysiology, the cardiorenal syndrome (CRS) is more often diagnosed and better managed. The echocardiographic evaluation of CRS now benefits from three-dimensional speckle tracking echocardiography (3D-STE), which allows multidimensional and real-time evaluation of regional myocardial and overall cardiac function, and helps assessing the degree of myocardial damage. This article describes the application of 3D-STE in evaluating the myocardial motion in patients with CRS.     

Elimination of myeloma cells from bone marrow by using monoclonal antibodies and magnetic immunobeads

The efficacy of immunomagnetic beads to purge human myeloma cells from bone marrow ex vivo was evaluated. The optimal conditions for purging were studied first by using three myeloma cell lines: RPMI-8226, SKO- 007, and SKMM-2. Myeloma cells labeled with the vital fluorescent dye Hoechst 33342 were admixed with normal bone marrow cells, and two monoclonal antibodies reactive with the myeloma cells (PCA-1 and BL-3) were added alone or in combination with the cells. Magnetic beads coated with goat antimouse immunoglobulin G were then added, and the tumor cells to which beads were attached were separated from the mixture with a magnet. The efficacy of tumor cell removal was dependent on the bead-to-tumor ratio; a ratio of more than 500 was optimal in the presence of excess normal marrow cells. The combination of monoclonal antibodies PCA-1 and BL-3 increased the tumor cell removal as compared with either antibody alone. Two cycles of treatment were more effective than one cycle was. Under optimal conditions, 2.3 to 4 logs of tumor cells could be removed from the mixture containing 10% myeloma cells without a significant loss of normal hematopoietic progenitors as measured by CFU-GM, CFU-GEM, and BFU-E. When the efficacy of this procedure was tested on fresh bone marrow from patients with multiple myeloma (MM) by using the combination of PCA-1, BL-3, and J-5, 1.6 to 2.5 logs of tumor cells could be removed by one cycle of treatment, even from marrows containing less than 10% myeloma cells. These observations support the use of monoclonal antibody combinations and immunobeads as a reliable and nontoxic method to eliminate contaminating myeloma cells ex vivo in preparation for autologous bone marrow transplantation in patients with MM.     

Molecular analysis of relapse in chronic myeloid leukemia after allogeneic bone marrow transplantation

Four patients with Philadelphia (Ph') positive chronic myeloid leukemia (CML) were studied before, after, and on relapse following allogeneic bone marrow transplantation (BMT). Southern analysis of DNA from cells collected before and at relapse after BMT was performed in order to investigate the origin of the leukemia at relapse. Using minisatellite probes we showed that the relapse occurred in cells of host origin in all four patients and this was confirmed with a Y chromosome specific probe in two male patients who had a female donor. Furthermore, using two probes for the breakpoint cluster region (bcr) on chromosome 22, we showed that leukemic cells at relapse bore identical rearrangements to those in the disease at time of presentation of each patient. We conclude that relapse in all four patients is due to re-emergence of the original leukemic clone.     

Construction and application of tuberculosis medical and nursing integration cooperation model

Objective

To explore the clinical effect of the tuberculosis (TB) doctor–nurse integration management model

Methods

This study is a retrospective historical cohort study. The clinical data of 180 patients with TB in our hospital from 2019 to 2020 were analyzed retrospectively. In a control group, 90 cases were treated with the traditional medical care model. An observation group of 90 cases received clinical diagnoses, treatments, and nursing under a doctor–nurse integration management model. Comparative analyses between the two groups were conducted on various aspects, including the awareness level of TB prevention and control, medication compliance and patient satisfaction. Comparisons between the two groups were evaluated using independent-sample t-tests or Chi-squared tests

Results

Compared with the control group, the knowledge awareness levels of TB prevention and medication compliance in the observation group were significantly higher (p < .05). The appointment waiting times and hospitalization times in the observation group were significantly lower than in the control group (p < .05). The total average satisfaction score of the patients in the observation group was significantly higher than in the control group (p < .05). Compared with the control group, the patients in the observation group were significantly more satisfied with their nursing methods, operating techniques, psychological techniques, service attitudes, and ward management (p < .05). In addition, in the observation group, medical–nursing relationships and doctor–patient communication were better than in the control group; additionally, the satisfaction of doctors with nursing work was also higher than in the control group, which was a statistically significant difference (p < .05)

Conclusion

The implementation of an integrated medical–nursing cooperation model for TB will help increase the awareness of health knowledge in patients with TB, improve patient medication compliance and enhance patient satisfaction.